1. Field of the Invention
The present invention is directed to a method for checking the plausibility of sensor signals, and to a device and a method for outputting a trigger signal.
2. Description of the Related Art
Methods and devices known from the related art for checking the plausibility of sensor signals ensure that in the event of a defective sensor element no undesirable behavior occurs in a system, in particular a safety system. Functionalities of the methods and devices are known, which vary depending on the measuring principle and/or type of sensor elements and/or sensor signals and/or the arrangement of the sensor elements. Normally, devices for checking the plausibility of sensor signals include two sensor elements, the plausibility of first sensor signals of a first sensor element being checked, and second sensor signals of a second sensor element being used to check the plausibility of the first sensor signals. If the first sensor signals of the first sensor element are recognized as plausible, then it is assumed that the first sensor element is not defective.
Published German patent application document DE 101 23 625 A1 describes a method and a device for monitoring a measured value acquisition of a physical quantity in which two redundant measured values of a physical quantity are present. In this case a first sensor element detects a first measured value and a second sensor element detects a second measured value. In checking the plausibility, the quotient of the two measured values is formed and is compared with a tolerance range. If a deviation of the quotient from the tolerance range is inadmissible, an error status of a sensor element is then assumed.
Published German patent application document DE 10 2004 042 467 A1 describes a method and a device for generating a trigger signal for a pedestrian safety device, which carry out a trigger and plausibility check of the sensor signals after a collision with an object is detected. In this method a feature extraction is carried out for detecting a pedestrian with the sensor signals which determines the point of impact of the object and a trigger signal for a pedestrian safety device is generated if, during a trigger check, a collision with a pedestrian is detected and the plausibility check of the sensor signals is positive. The device for checking the plausibility of the sensor signals compares the collision-related sensor signals with sensor signals of a central acceleration sensor unit.